Semiconductor device and method for fabricating the same

Abstract

A semiconductor device comprising: a storage electrode having a side wall forward tapered; a capacitor dielectric film formed on the side wall of the storage electrode; and a plate electrode formed on the side wall of the storage electrode with the capacitor dielectric film interposing therebetween, the plate electrode having a side wall inversely tapered.

What is claimed is:  
     
       1. A semiconductor device comprising: 
       an insulation film formed over a semiconductor substrate, the insulation film having an opening;  
       a storage electrode having a side wall forward tapered formed over the insulation film, the storage electrode being electrically connected to the semiconductor substrate via the opening;  
       a capacitor dielectric film formed on the side wall of the storage electrode and on the insulation film beneath the storage electrode; and  
       a plate electrode formed on the side wall of the storage electrode with the capacitor dielectric film interposing therebetween, the plate electrode having a side wall inversely tapered.  
     
     
       2. A semiconductor device comprising: 
       a first insulation film formed over a semiconductor substrate, the first insulation film having openings;  
       storage electrodes each having a side wall forward tapered formed over the first insulation film, each of the storage electrodes being electrically connected to the semiconductor substrate via the opening;  
       a capacitor dielectric film formed on the side wall of the storage electrodes and on the first insulation film beneath the storage electrodes; and  
       a plate electrode formed on the side wall of the storage electrodes with the capacitor dielectric film interposing therebetween, the plate electrode having a side wall inversely tapered.  
     
     
       3. A semiconductor device according to  claim 2 , wherein the first insulation film has a first film and a second film formed on the first film; 
       each of the storage electrodes is formed in the opening at the second film and electrically connected to the semiconductor substrate via a conductive plug buried in the opening at the first film.  
     
     
       4. A semiconductor device according to  claim 3 , wherein the conductive plugs are formed of the same conducting layer as the storage electrodes. 
     
     
       5. A semiconductor device according to  claim 3 , wherein the capacitor dielectric film is formed on the side wall of the openings. 
     
     
       6. A semiconductor device according to  claim 3 , wherein 
       the plate electrode is formed along the side wall of the storage electrodes and an upper face of the first insulation film,  
       a region between the storage electrodes is buried by the plate electrode and a second insulation film formed on the plate electrode.  
     
     
       7. A semiconductor device according to  claim 6 , further comprising: 
       an interconnection layer electrically connected to the plate electrode at a region where the plate electrode is formed along the upper face of the first insulation film.  
     
     
       8. A semiconductor device comprising: 
       a semiconductor substrate including a first region and a second region:  
       a capacitor formed in the first region including a storage electrode having a side wall forward tapered; a capacitor dielectric film formed on the side wall of the storage electrode; and a plate electrode formed on the side wall of the storage electrode with the capacitor dielectric film interposing therebetween, the plate electrode having a side wall inversely tapered; and  
       an interconnection layer formed in the second region and formed of the same conducting layer as the storage electrode, the interconnection layer is electrically connected to the semiconductor substrate in the second region or a conducting layer formed in the second region.  
     
     
       9. A semiconductor device comprising: 
       a semiconductor substrate including a first region and a second region;  
       a capacitor formed in the first region including a storage electrode having a side wall forward tapered; a capacitor dielectric firm formed on the side wall of the storage electrode; and a plate electrode formed on the side wall of the storage electrode with the capacitor dielectric film interposing therebetween, the plate electrode having a side wall inversely tapered; and  
       an interconnection layer formed in the second region and formed of the same conducting layer as the plate electrode, the interconnection layer is electrically connected to the semiconductor substrate in the second region or a conducting layer formed in the second region.